1. Field of the Invention
The present invention relates to improvements in an automatic medium changer, and in particular, to improvements in the automation of the lock/unlock mechanism of the door provided to the casing.
2. Related Art
An automatic medium changer, which is so configured as to selectively take an information storage medium out of multiple information storage media stored in the casing, and read/write data therefrom or thereto, has already been known.
By its nature, this kind of automatic medium changer includes, as essential requirements, a medium storing unit for storing multiple information storage media, a read/write unit for reading data from or writing data into the information storage media, and a carrier which reciprocates between the medium storing unit and the read/write unit while holding an information storage medium.
Since the information storage media stored in the casing are required to be exchanged with others of the outside, an openable door is provided to one surface of the casing. This permits an access to the medium storing unit from the outside.
However, if someone opens the door and put a hand into the casing when the carrier is moving between the medium storing unit and the read/write unit, a problem of the hand being caught in the operating carrier may be caused.
In order to solve such a disadvantage, some automatic medium changers, which are so configured as to prohibit inadvertent opening of the door when the carrier is moving, have been proposed.
For example, one that the door is locked using an electric actuator such as a solenoid to thereby prohibit an opening manipulation of the door when the carrier is moving, and one that an opening manipulation of the door by a hand itself is not prohibited, but by sensing the door being opened, a problem of a hand being caught or the like is prevented by forcibly stopping the movement of the carrier, have been known.
Further, one that the door is locked without using an electric actuator is disclosed in, for example, the Japanese Utility Model Application Laid-open No. 64-35544. In this publication, a cassette transferring device is proposed, which is so configured as to permit a cassette to be fed by releasing the lock of the open-close cover when the cassette feeding mechanism is activated, and the open-close cover is locked when the cassette feeding mechanism is inactivated. However, this only prevents an accident caused by the open-close cover being opened in the state of no cassette, and is not provided with a function of locking the open-close cover when the cassette feeding mechanism is activated.
However, a configuration, in which the door is locked using an electric actuator such as a solenoid, causes a problem that the manufacturing cost becomes relatively high. Further, a configuration, in which the movement of the carrier is forcibly stopped, may cause such problems as damages or overloads to the device by the forced stopping manipulation.